Drill seal



May 24, 1932. p YUNGLING DRILL SEAL Fi led Feb. 24, 1951 Jim. 1. j '1G..

Paul Kmyliny Patented May 24, 1932 UNITED PATENT oFFicE 1 PAUL YUNGLING, OE LOS ANGELES, CALIFORNIA, ASSIGNOR TO MONAiRCI-I OIL' WELL AIR DRILL CO. LTD;, OF RENO, NEVADA; A CORPORATION OF NEVADA DRILL SEAL Application filed February 24, 1931.

This invention relates to a seal for drills of the pneumatically operated type adapted for well drilling operations, and of the character set forth in my co-pending application for United States Letters Patent, Serial Number 402,835, filed October 28, 1929, which embodies a reciprocal ,bit' stem projecting from a drill shank carried ona rotary stem, and which drill is adapted to be operated in liquid containing well bores.

The primary object of the invention is the provision of a seal which will serve to prevent leakage of liquid from the well bore around the bit stem.

Another object is to provide a construction to minimize and off-set back pressures due to hydrostatic pressures when the drill is submerged in liquid and whereby the drill is rendered adaptable for use at considerable depths of submersion.

Another object is to provide a seal between the relatively movable bit stem and its mounting which may be readily applied and which may be quickly removed and replaced.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear the invention resides in the parts and in the combination, construction and arrangement of parts hereinafter described and claimed and illustrated by way of example in the accompanying drawings in which:

Figure 1 is a view in longitudinal section of the lower portion of a well drill with parts shown in elevation and showing the invention as applied with the bit stem disposed in its retracted position;

Figure 2 is a view similar to Figure 1 but showing the bit stem in its advanced position;

Figure 3 is a detail in horizontal section taken on the line 33 of Figure 1;

Figure 4 is a view in horizontal section taken on the line 4-4 of Figure 2.

Referring to the drawings more specifical- 1y, A indicates generally the lower end portion of a drill shank which is here shown as including an end section 6 above which is disposed a reciprocal hammer or ram 7 which may be operated in any desired manner, but

Serial No. 517,881.

is preferably actuated by fluid pressure in a conventional fashion. Carried by the shank section 6 is a reciprocal stem 8 fitted at its lower end with a bit '9 and the upper end of which stem projects into arecesslO formed in the lower end of the section 6, and which stem is fitted with a head 11 on which is seated a striking pin 12 guided in an opening 13 leading upwardly from the chamber 10 through the section 6 whereby the upper end of the pin 12 is disposed to project into the path of travel of the ram 7. A spring 14 is wound around the stem 8 and bears against the underside of the head 11 to normally maintain the stem 8 in its retracted position, as shown in Figure 1.

In: carrying out the present invention, a

tubular projection 15 is provided on the lower end of the drill shank which is here shown as comprising a nipple which is screwed into engagement with the lower end of the chamber 10 by a threaded joint 16. The bore of the projection 15 is lined with asuitable sleeve or bushing 17 the upper end of which is formed with a flange 18 arranged to seat against a shoulder 19 formed on the wallof the chamber '10. The lower end portion of the projection 15 is tapered inwardly and converges to a thin edge 201at the lower endthereof and beyond which the lower end portion of the sleeve 17 projectsand which sleeve is likewise-tapered to extend in continuation of the taper of the projection 15 to terminate in athin edge 21 which latter con stitutes the lower margin of the tubular projection l5.

An important feature of the invention resides in forming the stem 8 with a depres sion', here shown as comprising an annular or circumferentially extending channel 22 of arcuate cross section. This: channel 22 is located at such point on the length of the stem 8 that when the latter is'in its retracted position the lower margin of the channel will.

be disposed substantially in line with the lower edge 21 of the tapered projection formed by the nipple and sleeve, and is of such width that when the stem is disposedin its" lowermost position, as shown in Figure 2, the upper-margin of said channel will be disposed substantiall in line with the lower end 21 of the tapere projection.

The volumetric capacity of the space formed by the channel 22 in the circumferential plane of the stem 8 is designed to correspond, or at least nearly correspond, to the volumetric displacement of liquid effected by advancing and retracting the stem while submerged.

Encircling the lower end portion of the projection 15 and extending over the protruding end portion of the stem 8 is an elastic sleeve 23 the upper end portion of which is here shown as aflixed to the projection 15 by means of a clamp 24 and is aiiixed at its lower end portion to the protruding end of the stem 8 by a clamp 25. Peripheral flanges 26 and 27 are formed on the projection 15 and the stem 8 to cooperate with the clamps 24 and 25 in effecting secure connection between the sleeve 28 and the projection and shank and also to insure the formation of liquid tight joints therebetween. The elastic sleeve 23 is formed with its inner surface arranged to closely conform to the contiguous surfaces of the projection 15 and stem 8.

In the operation of the invention, the stem 8 is advanced longitudinally in one direction from the position shown in Figure 1 to the position shown in Figure 2 by impact of the ram or hammer 7 on the pin 12, and is restored to its normal retracted position under the urge of the spring 14. As the stem 8 moves downwardly liquid within which the drill is submerged, indicated at B in Figure 2, which is displaced by downward movement of the stem will, under its hydrostatic head, press the sleeve 23 inwardly into the recess 22 thereby forming said sleeve with a channel C around the exterior thereof having a volumetric capacity corresponding, or substantially corresponding to the amount of liquid displaced by movement of the stem, thus relieving the stem of back pressures due to hydrostatic pressure of the liquid. On retraction of the stem 8, the walls of the recess 22 will force the portion of the sleeve abutting thereagainst outwardly thereby displacing liquid then in the recess formed in the sleeve which liquid will then move to occupy the space previously occupied in the liquid by the stem.

In this manner, on reciprocation of the stem, the liquid displaced thereby, which equals in volume the cubic content of the portion of the stem moved in and out of the surrounding liquid, that is, the cross sectional area of the stem multiplied by the length of its stroke; the liquid thus displaced surging back and forth contiguous the stem and bit irrespective of the hydrostatic head of the liquid in the well 4.

While I have shown and described a specific. embodnnent of my invention, I do not limit myself to the exact details of construction and arrangement shown, but may employ such modification of the parts and changes in the details thereof as come within the meaning and scope of the appended claims.

I claim:

, 1. In a drill, a drill shank, a drill stem protruding from said shank, a bit on said stem, means for reciprocating said stem, and an elastic sleeve connected to said stem to encompass the protruding portion of the .stem and afiixed relatively to said drill shank to afford a liquid tight seal between said stem and shank, said shank being formed with an external channel, a tube interposed between said channel and said elastic sleeve when the stem is disposed in a retraced position, said channel being arranged to receive portions of said elastic sleeve under external pressures applied thereto when said stem is in an ad vanced position.

In a drill, a drill shank, a tapered tubular projection on said shank, a fixed stem reciprocally mounted in said projection and protruding therefrom, means for reciprocating said stem, a recess formed on said stem normally covered by said projection when said stem is in a retracted position and disposed to extend exteriorly of said stem when said stem is in an advanced position, and an elastic sleeve encompassing said projection and a part of the protruding portion of said stem; said sleeve being afiixed at its end portions to said projection and stem.

PAUL YUNGLING. 

